Light writing type projection display using polymer-dispersed liquid crystal and liquid crystal television set as image light source

摘要

A light writing type projection display for inputting two- dimensional information such as images or data patterns into a spatial light modulator by using a write light beam, and displaying the information on a screen by using a display light beam. The projection display comprises a light write type spatial light modulator, and either a cathode ray tube or a liquid crystal television set. The modulator includes an antireflection film, a glass substrate, a transparent electrode, a liquid crystal composition, a dielectric mirror, a light absorption layer, a photoconductive layer, a transparent electrode and a fiber optic plate which are laminated in the recited sequence. The liquid crystal composition includes one of a nematic liquid crystals, cholesteric liquid crystals, and smectic liquid crystals combined with a resin matrix. The resin matrix has a refractive index equal to or approximately equal to the ordinary or extraordinary refractive index of the liquid crystals, or equal to or approximately equal to the refractive index of the randomly oriented liquid crystals. The liquid crystals are enclosed and scattered in the resin matrix, or the resin matrix is enclosed and scattered in the liquid crystals. The projected light beam is thrown on a screen by using a display beam light source and the projection optical system. Compared with the conventional displays, the display is superior in brightness, contrast ratio, spatial uniformity of the display image and response time. Analog motion images can be displayed by using a schlieren optical system.